fix OOIION-1372

Fix https://jira.oceanobservatories.org/tasks/browse/OOIION-1372

A relevant test  continues to be ion/agents/platform/test/test_platform_agent_with_rsn.py:TestPlatformAgent.test_resource_monitoring

but there is *no* specific integration test that verifies the fix. Working on it. Feel free to postpone merging but please review.

@MauriceManning please review